Add shared workflow for build docs

.github/workflows/build_PR.yml

@@ -0,0 +1,17 @@
+name: Build Docs (Self)
+
+on:
+  pull_request:
+    paths:
+      - '.github/workflows/build_docs.yml'
+      - '.github/workflows/build_PR.yml'
+
+
+jobs:
+  build-docs:
+    uses: ./.github/workflows/build_docs.yml
+    with:
+      main-repo: napari/napari
+      main-ref: main
+      docs-repo: napari/docs
+      docs-ref: main

.github/workflows/build_docs.yml

@@ -0,0 +1,87 @@
+name: Build PR Docs
+
+on:
+  workflow_call:
+    inputs:
+      main-repo:
+        required: true
+        type: string
+        description: 'The main code repository (e.g. napari/napari or napari/docs)'
+      main-ref:
+        required: true
+        type: string
+        description: 'The ref (branch/sha) to use for the main repo (e.g. PR branch or main)'
+      docs-repo:
+        required: true
+        type: string
+        description: 'The docs repository (e.g. napari/docs)'
+      docs-ref:
+        required: true
+        type: string
+        description: 'The ref (branch/sha) to use for the docs repo (e.g. PR branch or main)'
+      make_target:
+        description: "Enter make target: html html-noplot docs slimfast slimgallery"
+        type: string
+        default: "slimfast"
+  workflow_dispatch:
+
+jobs:
+  build-and-upload:
+    name: Build & Upload Docs Artifact
+    runs-on: ubuntu-latest
+    env:
+      XDG_CACHE_HOME: ${{ github.workspace }}/.cache
+    steps:
+      - name: Checkout docs repo
+        uses: actions/checkout@v5
+        with:
+          repository: ${{ inputs.docs-repo }}
+          ref: ${{ inputs.docs-ref }}
+          path: docs
+      - name: Checkout main repo
+        uses: actions/checkout@v5
+        with:
+          repository: ${{ inputs.main-repo }}
+          ref: ${{ inputs.main-ref }}
+          path: napari
+      - name: Install the latest version of uv
+        uses: astral-sh/setup-uv@v6
+        with:
+          version: "latest"
+          python-version: '3.12'
+          activate-environment: true
+      - name: Cache pooch downloads
+        uses: actions/cache@v4
+        with:
+          path: |
+            ${{ github.workspace }}/.cache/scikit-image
+            ${{ github.workspace }}/.cache/napari-*
+            ${{ github.workspace }}/.cache/pooch
+          key: pooch
+      - name: Setup headless display
+        uses: pyvista/setup-headless-display-action@v4.2
+        with:
+          qt: true
+          wm: herbstluftwm
+      - name: Install dependencies
+        run: |
+          uv pip install --upgrade pip
+          uv pip install "napari/[pyqt5]" --group napari/pyproject.toml:docs
+        env:
+          UV_CONSTRAINT: ${{ github.workspace }}/napari/resources/constraints/constraints_py3.12_docs.txt
+      - name: Test import
+        run: |
+          python -c 'import napari; print(napari.__version__)'
+          python -c 'import napari.layers; print(napari.layers.__doc__)'
+      - name: Build docs
+        run: make -C docs ${{ inputs.make_target }}
+        env:
+          GOOGLE_CALENDAR_ID: ${{ secrets.GOOGLE_CALENDAR_ID }}
+          GOOGLE_CALENDAR_API_KEY: ${{ secrets.GOOGLE_CALENDAR_API_KEY }}
+          PIP_CONSTRAINT: ${{ github.workspace }}/napari/resources/constraints/constraints_py3.12_docs.txt
+          UV_CONSTRAINT: ${{ github.workspace }}/napari/resources/constraints/constraints_py3.12_docs.txt
+      - name: Upload artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: html
+          path: docs/docs/_build/html